What is planetary geology?

Planetary geology is a planetary science discipline concerned with the geology of celestial bodies, such as planets and their moons, asteroids, meteorites and comets.

Image Source: https://www.popularmechanics.com/space/a16443/solar-system-planets-pictures/

It is devoted to the study of structure, composition, processes, and origin of major and minor planetary bodies outside the solar system, and to the effects of interaction between planetary bodies within the solar system

Planetary geology consists of many fields; such as mathematics, astronomy, biology, chemistry and physics.

The goal of planetary geology is to understand the origin of the features seen on planets through sampling rocks, investigating superposition relationships and investigating impact-crater densities.

Some large body impact events, such as comets and meteorites hitting planets, have been strongly connected to mass extinctions of life on Earth, a driving force in evolutionary change. This is an example of the importance of planetary geology. Some large body impact events, such as comets and meteorites hitting planets, have been strongly connected to mass extinction of life on Earth, a driving force in evolutionary change. This is an example of the importance of planetary geology.

What do planetary geologists do?

Planetary geologists study planets and their rocks in many different ways: for example there is a wide range of professions within this, such as mineralogy, volcanology, oceanography, glaciology and stratigraphy.

The study of the geologic evolution of these planets in the observable universe is mainly performed by analyzing spacecraft observations (imagery, hyperspectral, radar or geophysical data) together with data gathered by robotic missions on the surface. Even so, to understand the geological processes that shaped other worlds, astrogeologists must also study the similar processes on our planet.

The study of the geologic evolution of these planets in the observable universe is mainly performed by analyzing spacecraft observations (imagery, hyperspectral, radar or geophysical data) together with data gathered by robotic missions on the surface. Even so, to understand the geological processes that shaped other worlds, astrogeologists must also study the similar processes on our planet.

Example of findings by plantary geologists

Titan:

Saturn’s largest moon, Titan, is an icy world whose surface is completely obscured by a golden hazy atmosphere. Titan is the second largest moon in our solar system. Only Jupiter’s moon Ganymede is larger by 2%.

Titan’s  internal structure isn’t entirely known, but one model based on data from the Cassini-Huygens mission suggests Titan has five primary layers. The innermost layer is a core of rock about 2,500 miles in diameter.

Image Source: https://www.airspacemag.com/daily-planet/saturns-moon-titan-living-cells-may-be-very-different-ours-180974104/

The surface of Titan is one of the most Earthlike places in the solar system, albeit at vastly colder temperatures and with different chemistry. Here it is so cold ( -179 degrees Celsius), that water ice plays the role of rock. 

Titan’s surface is sculpted by flowing methane and ethane, which carves river channels and fills lakes with liquid natural gas. No other world aside from Earth, has that kind of liquid activity on its surface.

Investigations in planetary geology

There are many examples of how scientists investigate space, below are a few:

Hubble space telescope – First launched in 1990 in low earth orbit, it still remains in operation and it orbits outside the distortion of the atmosphere of Earth, allowing it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. 

It has recorded some of the most detailed visible light images, allowing a deep view into space. Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe. On the 4th June 2021, it captured a very detailed image of a galaxy (NGC 691).

https://www.nasa.gov/image-feature/goddard/2021/hubble-images-a-galaxy-in-dazzling-detail

Curiosity Rover – Launched 26 november 2011, it landed on Mars on the 6th August 2012. The rover’s goals include an investigation of the Martian climate and geology of Mars. Also, an assessment of whether Mars has ever offered environmental conditions favorable for microbial life and planetary habitability in preparation for human exploration.

Closing words

Every day research into space advances using new technologies, producing inspiring breakthroughs that will help understand our solar system more. Scientists constantly make findings that we thought would never be possible, but as our universe is always expanding more work needs to be done before parts of the universe become unreachable. 

Thank you for reading and I hope you enjoyed it!

Written by Malick, a Year 11 Student at Haberdashers’ Aske’s Knights Academy